The aim of this project is to ultimately develop novel therapeutic agents for the treatment of cancer. The proposed agents are based on the use of a radiolabeled monoclonal antibody bearing the isotope, rhenium-188. This isotope is a generator produced item which could be used in any nuclear pharmacy in a rapid manner to give injectable material, and carrying a gamma emission as well as a beta emission can be used as a visualizing agent on SPECT. Antibodies will be labeled with this isotope using direct labeling technology and tested for efficacy in suitable animal models. The most effective format for rhenium antibody will be determined by these studies, prior to Phase II work on dose escalation and tolerability followed by initial clinical studies. Development work on the product(s) will be carried out in the second phase given good clinical results, and at the end of Phase II, multi-center clinical trials and a Phase III IND are to be expected. It is envisaged that the products final design will be simple enough to allow on-site one-step radiolabeling a trained nuclear medicine technologists, with the minimum of analytical validation, and then be ready for immediate patient use.